Articles combining sponge rubber and fibrous material and method of producing the same



Dec.14,1926.' 1,610,286

' H. M.- HOOD ET AL ARTICLE COMBINING'SPONGE RUBBER AND FIBROUS MATERIAL AND METHOD OF PRODUCING THE SAME v Filed August 12, 1924 Patented Dec. 14, 1926. I

UNITED; STATES nanny M. noon AND FRANK v. wnnLoox, or balance, ILL'INoIs,.Ass1eNons TO A 1,610,286 PATENT OFFICE.

FEATHEREDGE RUBBER COMPANY, INQfA CORPORATION OF ILLINOIS.

ARTICLES COMBIN IN G SPONGE a plication filed August 1z,'1a2 4. sees in." 731,640.

Our invention relates to a method of form-' ing' articles having a curved surface and which are made up. at least in part, of sponge rubber to which is united a surface layer of flexible fibrous material such as cloth, felt, leather or the like. This invention is based on the discovery that the swelling action and the pressure exerted by the sponge rubber during the process of vulcanizationcan be used to stretch the fibrous covering material to the" desired curved or.

irregular shape. The heat used to cause the. vulcanization may also to some extent assist (10. stretch. I

In carrying out our invention, sponge rubber compound is prepared in the manner understood by those skilled in the art, and shapedso that it may readily be the desired mold. If the surface 0 the rubber has been coated with soapstone or the like it may be wiped with kerosene or other substance ordinarily used forclea'nin the surface of rubber compounds and the fi ous material is spread over the rubber and pressed into place as smoothly as can be done. The compound with the covering material is then placed in the mold, which preferably is so constructed that the edges of the covering material will be held in place by the mold members. The mold is then placed in the usual steam vulcamzer press and subjected to the appropriate heat to efl'ect the desired cure. This heat causes the rubber compound to swell with considerable pressure so that the fibrous material is stretched, preferably to conform with the shape of the mold. The material is, of course, held in this position until the rubber is fully cured, so that when the mold is opened the finished article will be found to be formed to the desired shape, with the cover fully stretched and held in place by the close bond which the rubber has made with it during the course of vulcanizatmn.

By this process many useful articles may be made, such, for example, as chair cushions, which may be shaped so that the edges are beveled or curved and covered by the surface material.

A manner of carrying out our invention, as applied to a chair cushion WhlCll is taken as an illustrative example, is shown in the accompanying drawings, in which permit the fibrous, material to laced in 1 Fig. 1 shows a finished article, exceptthat the edges are untrimmed, a piece of the article elng broken away to show the connunnnnnun rnmous MATERIAL. AND ianriron or rnonucmo THE sun struction; Fig. 2- is a section through the mold showing the relation of the parts prior to the vulcanizi'ng operation, and Fig. 3 is a .view, similar to Fig, 2 showing the condition ofthe parts after the vulcamzingoperatlon. Y

In carrying out the manufacture of a chair cushion," a sheet ofstock roperly compounded so that sponge rubber will result after curing,'is laid on a flat table and the surface wiped with kerosene or other material adapted to clean the surface of the rubber. A piece of covering material such as felt. leather or the like is laid on the sheet of stock and pressed smoothly-in'place."

The mold has a lower part 2 formed with a concavity .inits upper surface and a fiat upper part 3. The rubber stock with the covering of felt or the like is then laid in the concavityand allowed to assume a natural position, the edges of the stock projecting over the edgesof the mold. The cover 3 is then p'utin place and forced-down against the lower portion 2. This will squeeze out the rubber that lies between the members 2 and 3, a portion being squeezed back into.

the mold cavity and the rest being sq eezed out at the edges. In Fig. 2 the sheet of rubber stock is designated by the numeral 4 and the covering is designated by the numeral 5.. The excess rubber squeezed from the mold may be removed and reused. The mold is then heated by any appropriate means to the proper temperature to eflect the desired cure and the heat is maintained the pro er length of time. This temperature an time will depend upon thenature of the compound used, as is well understood by those skilled in the art of making sponge rubber.

As shown inFig. 2 the 'stockand cover do not fill the mold cavity between the members 2 and 3, but as the stock is vulcanized it swells largely and entirely'fills the mold cavity. At the same time 'suflicient pressure is exerted by the swelling rubber to stretch the cover until it conforms to the shape of the mold cavity in member 2. This stretching may in part be assisted by the heat of the mold. In Fig. 3 the cover ance of the mold is shown as filled with sponge rubber designated. b the numeral '6.

In Fig. 1 the product is's own as it comes out of the mold. This comprises a body portion 6 of s nge rubber witha cover 5 firmly attache to it. A covering 5 may be used .for attaching the cushion to an article, or the ed s maybe trimmed of! and used as a portab e cushlon. In either event 1 edges of therubber cushion.

fibrous material, which comprises the steps of putting a sheet of fibrous material and it is to be noted-that the cover is stretched in place and follows smoothly the beveled a rubber compound adapted to swell when heated in a mold in such a way that the fibrous material must be stretched in order to conform to the shape of the desired article, and heating the mold while holdin the edges of the sheet of fibrous material, w ere-.

by the rubber compound is caused to swell.

and thereby stretch the fibrous material to the desired form and at the same time the I rubber is caused to adhere to the fibrous material.

2. A cushion comprising a sheet of spongerubber having beveled edge portions and having one surface, including such edge portions covered smoothly with fibrous material which is stretched to conform to such surface and which is united thereto by vulcanization and having theeother surface uncovered.

HARRY M. HOOD. FRANK V. WEDLOCK. 

